Since Live Aquaria posted the Blue Line Angelfish (Chaetodontoplus septentrionalis) on the Diver’s Den section, there has been great interest in this attractive and relatively rare species. This striped beauty can be found in Southern Japan at the Izu Islands, South Korea, Taiwain, Hong Kong and Vietnam. Recently many of these have been coming from [...]
Since Live Aquaria posted the Blue Line Angelfish (Chaetodontoplus septentrionalis) on the Diver’s Den section, there has been great interest in this attractive and relatively rare species. This striped beauty can be found in Southern Japan at the Izu Islands, South Korea, Taiwain, Hong Kong and Vietnam. Recently many of these have been coming from Vietnam, but every now and then collectors in Japan find juveniles in very shallow water that are brought in.
Specimens from Vietnam often have unique and intricate striped patterns on the face.
Juveniles are marked with an overall black body, with a yellow vertical band that runs just behind the eye and travels the full length of the body from the beginning of the dorsal to the pelvic fins. As the fish matures, the infamous blue lines fill in and the black and yellow markings fade.
Via Fishpix, K. Sorita
Juveniles and Sub-Adults often adapt quickly to captivity, but are much more rare then their older brothers and sisters. Like others from the Pomacanthidae Family, if you are considering purchasing one look for a specimen that is eating and in the 3″-5″ range. All to often these fish come in at 6″+ and refuse to eat.
This species can be extremely stubborn and it’s not uncommon for them to go on hunger strikes for months. Although the fish below has been offered everything from live foods to clam on the half shell, this 8″ Vietnam specimen at Old Town Aquarium in Chicago, has not eaten anything beyond the occasional microalgae for over 2 months! Despite this, the specimen is still active and does not have the tragic sunken belly that one would expect.
Sidenote: It has also been said that this species has been captive raised in “fish ponds” along with P. maculosus and P. asfur in Taiwan. The company that does breed this is extremely secretive of their practices and I have not heard of any captive bred C. septentrionalis in some time. Right now the popular export from this outfit is the white morph P. maculosus.
Should you have a Blue Line the refuses to eat, I would suggest trying some of the foods below:
- Clam (On the half shell, or cracked open)
- Scallop
- Live Sponge
- Damaged Fleshy LPS Corals
- Zoanthids
- Macro Algae e.g. Gracilaria
In my younger LFS days, I was able to wean a Blue Line on to prepared foods with the help of Zoanthids. If it were not for the polyps, the fish would have died months before accepting any real food. Although expensive, these meals are can be the only food and energy source stubborn adults may accept upon initial acclimation to captivity.
Once acclimated Chaetodontoplus septentrionalis can do extremely well and become very personable; the biggest obstacle to overcome with larger specimens is getting them to eat! Don’t be surprised if more of these begin popping up in the US market as aquarists become willing to foot the $200-$500 price that this fish often commands.
